Question: Tiffany ate 3 slices of cake. Christopher ate 4 slices. If there were initially 10 slices, what fraction of the cake was eaten?
$\text{fraction of cake eaten} = \dfrac{\text{number of slices eaten}}{\text{number of slices total}}$ They ate ${7}$ out of $10$ slices. They ate $\dfrac{7}{10}$ of the cake.